AI Tool Hub

JWT Decoder

Decode JWT header and payload in the browser.

Guide & how to use

What this tool does

Paste a JSON Web Token to Base64url-decode the header and payload, pretty-print JSON, and see expiry countdown. Does not verify signatures.

Example input/output

Illustrative sample — your real inputs may look different.

Example input

eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiIxMjMifQ.sig

Example output

Header: {"alg":"HS256"} · Payload: {"sub":"123"} · (signature not verified)

Frequently asked questions